Resilient sector plate for rotary regenerative heat exchanger



1963 G. E. FLURSCHUTZ 3,100,014

RESILIENT SECTOR PLATE FOR ROTARY REGENERATIVE HEAT EXCHANGER FiledSept. 19, 1960 United States Patent 3,100,014 RESILENT SECTOR PLATE FURRUTARY REGENERATIVE HEAT EXCHANGER Glenn E. Flurschutz, Wellsville,N.Y., assignor, by mesne assignments, to Combustion Engineering, Inc, astock corporation of Delaware Filed Sept. 19, 1960, Eer. No. 56,732 2Claims. (Cl. 165-9) The present invention relates to improvements inregenerative heat exchange apparatus of the rotary type, andparticularly it relates to a novel arrangement that substantiallyeliminates the leakage of fluid between areas of high and low pressure.

In rotary regenerative heat exchange apparatus a cylindrical rotorhaving sector shaped compartments carrying a mass of heat exchangeelement is rotated alternately between spaced streams of .a heatingfluid and a fluid to be heated in order that heat from the heating fluidmay be continuously transferred to the fluid to be heated through theintermediary of the heat absorbent element mass. The rotor is surroundedby a cylindrical housing having end or sector plates at opposite endsformed with spaced apertures between imperforate portions of sector-ialconfiguration that provide for the spaced flow of fluids through therotor. To prevent mingling of the heating fluid and the fluid to beheated, radial partitions of the rotor that form the sectorial rotorcompartments are provided with radial seals that wipe against theimperforate portions of the sector plates.

Frequently, thermal and mechanical forces combine to warp or deform therotor and the rotor housing to the extent that it becomes impossible tomaintain a satisfactory sealing relationship between the relativelymoving parts that precludes fluid flow therebetween. Therefore, thepresent invention is directed to a sealing arrangement that effectivelyprecludes leakage of fluid between relatively movable parts of the rotorand rotor housing. More particularly the invention relates to a uniquesector or end plate arrangement that is made axially flexible to conformreadily to variations in the axial spacing between the ends of the rotorand the confronting housing structure.

The invention will be better understood upon consideration of thefollowing detailed description of an illustrative embodiment thereofwhen read in conjunction with the accompanying drawings in which:

FIGURE 1 is a sectional side elevation of a rotary regenerative heatexchanger utilizing the principles of the invention.

FIGURE 2 is a fragmentary top plan view of the sector plate.

FIGURE 3 is a sectional elevation of the sector plate as seen from line3-3 of FIGURE 2.

In FIGURE 1 of the drawing the numeral designates a rotor having acylindrical rotor shell 12 divided into sector shaped compartments byradial partitions 14 that extend between a central rotor post 16 and therotor shell 12. The rotor is rotated slowly about its axis by a motorand reduction gearing arrangement that is diagrammatically illustratedat 18. The rotor compartments are filled with a mass of regenerativeheat exchange material in the form of spaced metallic plates or othermaterial that first ab sorbs heat from hot gases entering the heatexchanger through a duct 24 from a boiler or other source of heat to bedischarged after passing over the heat exchange element through anoutlet duct 26 to which an induced draft fan (not illustrated) isconnected. As the rotor turns slowly about its axis, the element thathas been heated by the hot gases in duct 24 is moved into a stream offluid to be heated that enters through a duct 28. After passing over theelements and absorbing heat therefrom, the heated 3,100,014 PatentedAug. 6, 1963 ice 2 fluid is discharged through a duct 32 and directed toa boiler furnace or other point of use.

A housing 34 enclosing the rotor shell 12 is provided at either endopposite ends of the rotor shell with upper and lower end or sectorplates 36 and 38 which are apertured at 39 and 40 in circumferentiallyspaced locations to admit and discharge streams of the heating fluid andthe fluid to be heated that flow through the rotor. In order that thestreams of heating fluid and fluid to be heated may not commi ngle, theend plates 36 and 38 have imperforate portions 42 located between theopenings that are at least equal to or somewhat greater incircumferential extent than one rotor compartment. The imperforate plate42 cooperates with the radial seals 44 to isolate a single sectorialcompartment when it lies between the spaced fluid passageways. In orderthat the fluid streams may not bypass the rotor and flow through theannular space between the rotor and its housing, circumferential sealsare provided on the shell 12 which cooperate with the confronting faceof an adjacent end plate to seal off the annular space between the rotor10 and its concentric rotor housing from the circulating fluids.

In present practive the circumferential seal and the radial sealingleaves are customarily formed from strips of thin metallic material thattheoretically conform somewhat to variations in the configuration of theconfronting end plate in order that leakage of fluid through theclearance space therebetween may be reduced to a minimum. Actuallyhowever, such sealing leaves tend to flex little during operation exceptfor that which occurs in accordance with the thermal deformation of therotor structure to which they are attached.

This invention however provides a composite flexible sealing surfacesuspended in a plane between the end edge of the rotor and theconfronting face of the adjacent end plate that conforms readily tovariations in configuration of the sealing leaves to preclude the flowof fluid therebetween.

In accordance with the invention the flexible sealing surface comprisesessentially the overlapping end flanges 48 of a series of sealing leaves52 that are attached in a substantially radial arrangement to theimperforate portion of each end or sector plate 42. The sealing leavescomprise essentially a web portion 54 having a flange 48 at one end andan oppositely extending flange 60 at an opposite end that provides meansthrough which a series of bolts or metal screws 56 are directed tosecure the sealing leaves to the sector plate. To facilitate removal andreplacement of the sealing leaves 52, alternate flanges 60 are sized topermit a single series of screws to adequately secure the flanges of apair of adjacent sealing leaves to the sector plate 42.

When securing the individual leaves 52 to the face of sector plate 42they are arranged with their overlapping flanges 48 facing in thedirection of rotor movement to preclude interference with the end edgeof the rotor and sealing means 44 as the rotor moves by. Furthermore, toinsure maximum resiliency of each sealing leaf, each web portion 54 isarranged to slope generally downward in the direction of rotor movementsuch that as the sealing means 44 approaches a sealing leaf '52 itsfirst area of contact is adjacent the curved portion that lies betweenthe web 54 and flange 48. To preclude leakage of the heating fluid orthe fluid to be heated through the voids between the overlapping sealingleaves 52, the sealing leaves are adapted to radially overlap the innerand outer arcuate edges of the sectorial compartments formed between theradial partitions 14.

In operation, rotating of the rotor 10 will advance the radial seals 44successively into contact with the sealing leaves 48, and depending uponthe extent of thermal distortion present in the rotor and adjacent endplates 42,

each leaf will flex accordingly to permit passage of the -radial seals.44. As each leaf fleXes it abuts-an adjacent leaf which then flexessimilarly but to a lesser extent, such that the composite surface thatcomprises the over- :zlappingle'aves ;48'.assurnes a somewhat undulatedconfiguration in continuous contact with .the end .edges of the radialseals. 'M'oreover, due to the slope of web '54, ivthetlength or eachleaf, .and the lack ofabrupt bends in the. configuration of eachleaflflexure of each leaf is disuturbed evenly over a large area and aconcentration of stresstat any singlepoint is eliminated to therebypreclude over fatigue'and untimely failure.

While'this invention has been described with reference -*tothe singleembodiment illustrated in the drawing, it is :evident that variouschanges may be made without derparting from the spirit of the invention."It is therefore :intended that all'matter contained in the abovedescriprtionor shown intthe accompanying drawings shall beinnterpretedlas illustrative and not in a limiting sense.

What I claim is:

11. Rotary regenerative-heat exchange apparatus in- :cluding acylindrical rotor having s'ectorial compartments that carry a mass of.heat absorbent material alternately zbetwee'n av-heating fiuid'andafluid to be heated; a cylindricalf housing surrounding therotor-including end plates at opposite ends thereofrhaving aperturesbetween imperforate sector-shaped portions that alternately direct the 4heating fluid and the fluid to be heated through spaced compartments ofthe rotor; and a resilient sealing surface suspended from theimperforate portion of each end plate into sealing relation with theadjacent end of the rotor, said resilient surface comprising incombination a series of mutually overlapping radial flanges that extendbetween inner and outer edges of the rotor compartments; a resilient webfixedwto a radial edge of each flange and extending toward said endplate; a second flange fixed to a spaced radial edge of each resilientweb and extending therefrom in a plane substantially parallel to theoverlapping radial fianges; and means securing each of said secondflanges to the end plate to maintain the resilient 1 overlapping flangesin position as a composite sealing plate confronting the adjacent end ofthe rotor.

2. Rotary regenerative heat exchange apparatus as defined in claim 1wherein the resilient web slopes generally away from the end plate inthe direction of rotor movement.

References Cited in the file of this patent UNITED STATES PATENTS1,746,598 Ljungstrom ;Feb. 11, 1930 2,468,826 Karlsson et al. May 3,1949 2,549,656 Yerrick et al Apr. 17, 1951 3,011,766 Hess Dec. -5, 1961

1. ROTARY REGENERATIVE HEAT EXCHANGE APPARATUS INCLUDING A CYLINDRICALROTOR HAVING SECTORIAL COMPARTMENTS THAT CARRY A MASS OF HEAT ABSORBENTMATERIAL ALTERNATELY BETWEEN A HEATING FLUID AND A FLUID TO BE HEATED; ACYLINDRICAL HOUSING SURROUNDING THE ROTOR INCLUDING END PLATES ATOPPOSITE ENDS THEREOF HAVING APERTURES BETWEEN IMPERFORATE SECTOR-SHAPEDPORTIONS THAT ALTERNATELY DIRECT THE HEATING FLUID AND THE FLUID TO BEHEATED THROUGH SPACED COMPARTMENTS OF THE ROTOR; AND A RESILIENT SEALINGSURFACE SUSPENDED FROM THE IMPERFORATE PORTION OF EACH END PLATE INTOSEALING RELATION WITH THE ADJACENT END OF THE ROTOR, SAID RESILIENTSURFACE COMPRISING IN COMBINATION A SERIES OF MUTUALLY OVERLAPPINGRADIAL FLANGES THAT EXTEND BETWEEN INNER AND OUTER EDGES OF THE ROTORCOMPARTMENTS; A RESILIENT WEB FIXED TO A RADIAL EDGE OF EACH FLANGE ANDEXTENDING TOWARD SAID END PLATE; A SECOND FLANGE FIXED TO A SPACEDRADIAL EDGE OF EACH RESILIENT WEB AND EXTENDING THEREFROM IN A PLANESUBSTANTIALLY PARALLEL TO THE OVERLAPPING RADIAL FLANGES; AND MEANSSECURING EACH OF SAID SECOND FLANGES TO THE END PLATE TO MAINTAIN THERESILIENT OVERLAPPING FLANGES IN POSITION AS A COMPOSITE SEALING PLATECONFRONTING THE ADJACENT END OF THE ROTOR.